Frequency biasing for doppler shift compensation in wireless communications systems

Abstract

Various aspects related to frequency biasing to compensate for frequency variations caused by Doppler shift in V2V communication systems are described. In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus, e.g., a UE, may be configured to determine a velocity of the apparatus, and determine a frequency biasing adjustment based on the determined velocity of the apparatus. The apparatus may be further configured to communicate with UE based on an adjusted carrier frequency determined based on a carrier frequency and the determined frequency biasing adjustment. In some configurations, a driving environment of the apparatus maybe considered, and the frequency biasing adjustment is determined further based on the determined driving environment.

What is claimed is: 
     
       1. A method of vehicle-to-vehicle (V2V) communication of a user equipment (UE), comprising:
 determining a velocity of the UE; 
 determining a frequency biasing adjustment based on the determined velocity of the UE and a tunable parameter separate from the determined velocity of the UE, wherein the tunable parameter is based on a driving environment of the UE; and 
 communicating with a second UE based on an adjusted carrier frequency that is adjusted based on a carrier frequency and the determined frequency biasing adjustment. 
 
     
     
       2. The method of  claim 1 , wherein the communicating comprises transmitting based on the adjusted carrier frequency that is adjusted based on the carrier frequency and the determined frequency biasing adjustment. 
     
     
       3. The method of  claim 1 , wherein the communicating comprises receiving based on the adjusted carrier frequency that is adjusted based on the carrier frequency and the determined frequency biasing adjustment. 
     
     
       4. The method of  claim 1 , wherein the adjusted carrier frequency is f ca  and the adjusted carrier frequency f ca  is determined based on f c +f ba , where f c  is the carrier frequency and f ba  is the frequency biasing adjustment. 
     
     
       5. The method of  claim 4 , wherein the frequency biasing adjustment f ba  is determined based at least on a factor equal to v/c, where v is the determined velocity and c is the speed of light. 
     
     
       6. The method of  claim 5 , wherein the frequency biasing adjustment f ba  is determined based on −a*(v/c)*f c , where a is the tunable parameter and 0≤a≤1. 
     
     
       7. The method of  claim 6 , further comprising:
 determining the driving environment of the UE; and 
 adjusting the tunable parameter a based on the determined driving environment of the UE. 
 
     
     
       8. The method of  claim 1 , further comprising determining the driving environment of the UE, wherein the frequency biasing adjustment is further determined based on the determined driving environment. 
     
     
       9. The method of  claim 8 , wherein the determining the driving environment of the UE comprises determining at least one of whether a road on which the UE is traveling is divided or undivided, a congestion of traffic headed in a same direction of the UE, a congestion of traffic headed in an opposite direction of the UE, a Global Positioning System (GPS) position of the UE, a map of an area associated with the GPS position of the UE, road conditions in the area associated with the GPS position of the UE, a history of collisions in the area associated with the GPS position of the UE, whether the UE is traveling on a road with an opposing traffic passing lane, or weather conditions in the area associated with the GPS position of the UE. 
     
     
       10. The method of  claim 9 , wherein the frequency biasing adjustment is determined further based at least on the tunable parameter a, where 0≤a≤1, the method further comprising:
 tuning a to a first value a 1  upon determining that the road on which the UE is traveling is divided; and 
 tuning a to a second value a 2 , where a 2 >a 1 , upon determining that the road on which the UE is traveling is undivided. 
 
     
     
       11. An apparatus for wireless communication, comprising:
 means for determining a velocity of the apparatus; 
 means for determining a frequency biasing adjustment based on the determined velocity of the apparatus and a tunable parameter separate from the determined velocity of the apparatus, wherein the tunable parameter is based on a driving environment of the apparatus; and 
 means for communicating with a user equipment (UE) based on an adjusted carrier frequency that is adjusted based on a carrier frequency and the determined frequency biasing adjustment. 
 
     
     
       12. The apparatus of  claim 11 , wherein the means for communicating is configured to transmit based on the adjusted carrier frequency that is adjusted based on the carrier frequency and the determined frequency biasing adjustment. 
     
     
       13. The apparatus of  claim 11 , wherein the means for communicating is configured to receive based on the adjusted carrier frequency that is adjusted based on the carrier frequency and the determined frequency biasing adjustment. 
     
     
       14. The apparatus of  claim 11 , wherein the adjusted carrier frequency is f ca , the apparatus further comprising:
 means for determining the adjusted carrier frequency f ca  based on f c +f ba , where f c  is the carrier frequency and f ba  is the frequency biasing adjustment. 
 
     
     
       15. The apparatus of  claim 14 , wherein the frequency biasing adjustment f ba  is determined based at least on a factor equal to v/c, where v is the determined velocity and c is the speed of light. 
     
     
       16. The apparatus of  claim 15 , wherein the frequency biasing adjustment f ba  is determined based on −a*(v/c)*f c , where a is the tunable parameter and 0≤a≤1. 
     
     
       17. The apparatus of  claim 16 , further comprising:
 means for determining the driving environment of the apparatus; and 
 means for adjusting the tunable parameter a based on the determined driving environment of the apparatus. 
 
     
     
       18. The apparatus of  claim 11 , further comprising means for determining the driving environment of the apparatus, wherein the means for determining the frequency biasing adjustment is further configured to determine the frequency biasing adjustment based on the determined driving environment. 
     
     
       19. The apparatus of  claim 18 , wherein the means for determining the driving environment of the apparatus is configured to determine at least one of whether a road on which the apparatus is traveling is divided or undivided, a congestion of traffic headed in a same direction of the apparatus, a congestion of traffic headed in an opposite direction of the apparatus, a Global Positioning System (GPS) position of the apparatus, a map of an area associated with the GPS position of the apparatus, road conditions in the area associated with the GPS position of the apparatus, a history of collisions in the area associated with the GPS position of the apparatus, whether the UE is traveling on a road with an opposing traffic passing lane, or weather conditions in the area associated with the GPS position of the apparatus. 
     
     
       20. The apparatus of  claim 19 , wherein the frequency biasing adjustment is determined further based at least on the tunable parameter a, where 0≤a≤1, the apparatus further comprising:
 means for adjusting the tunable parameter a, the means for adjusting the tunable parameter being configured to tune a to a first value a 1  upon determining that the road on which the apparatus is traveling is divided, and tune a to a second value a 2 , where a 2 >a 1 , upon determining that the road on which the apparatus is traveling is undivided. 
 
     
     
       21. An apparatus for wireless communication, comprising:
 a memory; and 
 at least one processor coupled to the memory and configured to:
 determine a velocity of the apparatus; 
 determine a frequency biasing adjustment based on the determined velocity of the apparatus and a tunable parameter separate from the determined velocity of the apparatus, wherein the tunable parameter is based on a driving environment of the apparatus; and 
 communicate with a user equipment (UE) based on an adjusted carrier frequency that is adjusted based on a carrier frequency and the determined frequency biasing adjustment. 
 
 
     
     
       22. The apparatus of  claim 21 , wherein the at least one processor is configured, as part of being configured to communicate, to transmit based on the adjusted carrier frequency that is adjusted based on the carrier frequency and the determined frequency biasing adjustment. 
     
     
       23. The apparatus of  claim 21 , wherein the at least one processor is configured, as part of being configured to communicate, to receive based on the adjusted carrier frequency that is adjusted based on the carrier frequency and the determined frequency biasing adjustment. 
     
     
       24. The apparatus of  claim 21 , wherein the adjusted carrier frequency is f ca , and
 wherein the at least one processor is further configured to determine the adjusted carrier frequency f ca  based on f c +f ba , where f c  is the carrier frequency and f ba  is the frequency biasing adjustment. 
 
     
     
       25. The apparatus of  claim 24 , wherein the at least one processor is configured to determine the frequency biasing adjustment f ba  based at least on a factor equal to v/c, where v is the determined velocity and c is the speed of light. 
     
     
       26. The apparatus of  claim 25 , wherein the at least one processor is configured to determine the frequency biasing adjustment f ba  based on −a*(v/c)*f c , where a is the tunable parameter and 0≤a≤1. 
     
     
       27. The apparatus of  claim 26 , wherein the at least one processor is further configured to:
 determine the driving environment of the apparatus; and 
 adjust the tunable parameter a based on the determined driving environment of the apparatus. 
 
     
     
       28. The apparatus of  claim 21 , wherein the at least one processor is further configured to determine the driving environment of the apparatus, and determine the frequency biasing adjustment further based on the determined driving environment. 
     
     
       29. The apparatus of  claim 28 , wherein the at least one processor is further configured, as part of being configured to determine the driving environment of the apparatus, to determine at least one of whether a road on which the apparatus is traveling is divided or undivided, a congestion of traffic headed in a same direction of the apparatus, a congestion of traffic headed in an opposite direction of the apparatus, a Global Positioning System (GPS) position of the apparatus, a map of an area associated with the GPS position of the apparatus, road conditions in the area associated with the GPS position of the apparatus, a history of collisions in the area associated with the GPS position of the apparatus, whether the UE is traveling on a road with an opposing traffic passing lane, or weather conditions in the area associated with the GPS position of the apparatus. 
     
     
       30. A non-transitory computer-readable medium of an apparatus, the computer-readable medium storing computer executable code, comprising code to:
 determine a velocity of the apparatus; 
 determine a frequency biasing adjustment based on the determined velocity of the apparatus and a tunable parameter separate from the determined velocity of the apparatus, wherein the tunable parameter is based on a driving environment of the apparatus; and 
 communicate with a user equipment (UE) based on an adjusted carrier frequency that is adjusted based on a carrier frequency and the determined frequency biasing adjustment.